Exodus 19:11

11 so that on the third day they'll be fully prepared, because on the third day God will come down on Mount Sinai and make his presence known to all the people.

Exodus 19:11 Meaning and Commentary

Exodus 19:11

And be ready against the third day
Not the third day of the month, but the third day from hence, this being the fourth, and the morrow the fifth, and the third day, the day following that, the sixth, on which day it is generally agreed by the Jews that the law was given, (See Gill on Exodus 19:16)

for the third day the Lord will come down in the sight of all the
people upon Mount Sinai;
which must be understood, consistent with his omnipresence, and is only expressive of some visible display of his power, and of some sensible token of his presence to the people; he was now upon it in the pillar of cloud, but then he would appear in another manner, and descend in a thick cloud and fire, which all the people would see, though they could not see the similitude of anything in it.

Exodus 19:11 In-Context

9 God said to Moses, "Get ready. I'm about to come to you in a thick cloud so that the people can listen in and trust you completely when I speak with you." Again Moses reported the people's answer to God.

10 God said to Moses, "Go to the people. For the next two days get these people ready to meet the Holy God. Have them scrub their clothes

11 so that on the third day they'll be fully prepared, because on the third day God will come down on Mount Sinai and make his presence known to all the people.

12 Post boundaries for the people all around, telling them, 'Warning! Don't climb the mountain. Don't even touch its edge. Whoever touches the mountain dies - a certain death.

13 And no one is to touch that person, he's to be stoned. That's right - stoned. Or shot with arrows, shot to death. Animal or man, whichever - put to death.' "A long blast from the horn will signal that it's safe to climb the mountain."